A banking service with "micro-accounts". E.g. each month I would put $80 in my "buy a new laptop every couple of years" account, and each day I would put $20 in

A banking service with "micro-accounts". E.g. each month I would put $80 in my "buy a new laptop every couple of years" account, and each day I would put $20 in my "feed and entertain myself" account. Every couple of years I could buy myself a laptop without getting a pointless "You spent $1500 on computing this month! You usually spend $10! Ermahgerd!1!!" alert. And when I'm thinking about treating myself to a night out, I can quickly see how guilty I should feel about doing so.